1. Field of the Invention
The present invention relates to an endoscope cover type endoscope using an endoscope cover for preventing the contamination of the endoscope.
2. Description of the Related Art
Recently, an endoscope for performing a diagnosis and treatment by inserting a slender inserting portion into a coelom is widely used. In a test performed by using an endoscope, a clean endoscope having been sufficiently rinsed and sterilized prior to the test must be used. Therefore, an endoscope contaminated by being used in the coelom of a patient is rinsed and sterilized by various methods before it is used to a next patient. However, it takes a very long time to completely and sufficiently rinse the endoscope.
To overcome this drawback, Japanese Examined Patent Publication No. Hei 2-54734, U.S. Pat. No. 3,162,190 disclose a disposable type endoscope cover type endoscope used in place of a repeatedly-usable type endoscope. These proposals intend to prevent the contamination of the endoscope by covering the endoscope with an endoscope cover. More specifically, the endoscope cover type endoscope according to these proposals is composed of an endoscope cover and an endoscope covering endoscope (hereinafter, referred to as a covering type endoscope), and the inserting portion of the covering type endoscope can be covered with the endoscope cover. Contamination of the covering type endoscope is prevented by inserting the covering type endoscope into the coelom of a patient while it is covered with the endoscope cover. Note, after the covering type endoscope is used, the disposable endoscope cover is removed and disposed of.
The inserting portion of the covering type endoscope includes, for example, a photographing system, observing optical system and light guide fiber. On the other hand, since a forceps channel, air and water feed pipes may be contaminated by body fluids and further are difficult to be rinsed and sterilized because they have a slender shape, these channels are integrally mounted to the endoscope cover and disposed of together with it. That is, the endoscope cover is provided with a channel for treatment tools and pipes having an opening at the opposite ends thereof such as air and water feed pipes. Note, an endoscope cover provided with a channel of endoscope covers may be referred to as an endoscope cover with a channel. Further, a covering type endoscope to be inserted into the endoscope cover with a channel may be referred to as an endoscope covering endoscope with a channel.
As described above, the rinsing and sterilization of the covering type endoscope can be made unnecessary by disposing an endoscope cover with a channel used to each patient, and thus this is very sanitary. Since the covering type endoscope need not be rinsed and sterilized, a test effected by using an endoscope can be continuously performed to a plurality of patients.
Incidentally, a repeatedly-usable type endoscope which is not covered with an endoscope cover (hereinafter, referred to as an endoscope without a cover) includes an indicator for indicating an inserting length at an inserting portion. This indication can be used as a yardstick for confirming an observing portion during a test and is also used when a portion changed to a morbid state is recorded.
However, in a conventional endoscope cover type endoscope, even if an indicator for indicating an inserting length is provided to the inserting portion of a covering type endoscope, the inserting portion cannot be visually confirmed because it is covered with the endoscope cover, and thus this indication cannot be used. Therefore, in the conventional endoscope cover type endoscope, the inserted length of the endoscope cannot be confirmed during a test, which is an obstruction for a test and a record of a portion changed to a morbid state.
Incidentally, recently, an ultrasonic endoscope for obtaining an ultrasonic cross sectional image by inserting an ultrasonic probe into a coelom such as a blood pipe is used for various diagnoses. An ultrasonic oscillator serving as an ultrasonic wave transmitter/receiver is provided at the extreme end of the ultrasonic prove inserted into the lumen to generate an ultrasonic wave for diagnosis and to receive an echo from an observing portion.
It is contemplated to use a disposable endoscope cover also for this ultrasonic endoscope. That is, the ultrasonic endoscope is used as a covering type endoscope (hereinafter, referred to as an ultrasonic covering type endoscope). Conventionally, however, an endoscope cover used to insulate the ultrasonic covering type endoscope from the outside is not different from that used for a covering type endoscope, such as an electronic or optical type fiber scope, and does not have a sufficient ultrasonic wave transmittance. Therefore, when the endoscope is covered with an endoscope cover, a drawback arises in that it cannot obtain an ultrasonic image.
In a test effected by using a usual ultrasonic endoscope not using an endoscope cover (with a channel), a deaerated water feed method or balloon method is used, taking into consideration that an ultrasonic wave is greatly attenuated in air. In the deaerated water feed method, a test is effected in the state that deaerated water is fed to a lumen, and in the balloon method, a test is effected in the state that deaerated water is fed to a balloon provided with an ultrasonic endoscope. Both methods remove an air layer causing the attenuation of an ultrasonic wave by filling the portion between a lumen wall and an ultrasonic wave transmitting/receiving unit with deaerated water, and a good ultrasonic image is obtained by effecting a test in this state.
When, however, the covering type ultrasonic endoscope is covered with the endoscope cover, an air layer is formed between the endoscope cover and the covering type ultrasonic endoscope, and thus a problem arises in that a good ultrasonic image cannot be obtained.
Incidentally, the inserting portion of the covering type endoscope has one end capable of being curved so that any desired direction can be observed and diagnosed, and a switch for the curving operation is disposed on the operating unit. Further, the operating unit is also provided with an air/water feed switch for controlling the feed of air and water through an air/feed pipe and also with a sucking switch for controlling the sucking operation for sucking bodily fluids and the like. Further, a function switch for photographing and the like is also disposed. In addition, a universal cord is connected to the operating unit on the hand side thereof and a slender inserting portion is connected to the extreme end side thereof.
Conventionally, there is a case in which the portion of an endoscope cover for covering the operating unit (hereinafter, referred to as an operating unit cover) is composed of a sheet member. Nevertheless, as described above, since many switches are disposed on the operating unit and further the universal cord and inserting portion are connected thereto, the operating unit is formed to have a very complicated configuration. Therefore, the method of covering the operating unit with the sheet-shaped operation unit cover makes a mounting job very time-consuming, and further when it is not correctly mounted, the operation unit may not be entirely covered.
Thus, a hard operating unit cover molded of hard plastic is proposed. The hard operating unit cover has an inner surface shaped substantially contrary to the outer surface of the operating unit and a structure to be divided into two parts. The operating portion cover can be mounted in such a manner that a pair of the operating portion covers are mated to each other with the operating unit held therebetween. That is, the workability of a mounting job is improved by using the hard operating unit cover and this operating unit cover is sufficient to entirely cover the operating unit. When, however, the operating unit is covered with the hard operating unit cover, a drawback arises in that a large force is required to operate the switches disposed on the surface of the operating unit and the operation thereof is difficult.
Incidentally, the curving portion at the extreme end of the inserting portion of the cover type endoscope is composed of a plurality of curving pieces connected to each other. A wire is connected to the curving piece at the most extreme end and pulled by rotating a curving knob disposed on the operating unit to curve the curving portion.
A curved knob cover for covering the curving knob to prevent the contamination thereof must be able to be rotated. Therefore, the curving knob cover has a complicated structure and a drawback arises in that the rotation of the curving knob is prevented by the curving knob cover depending upon the structure thereof.
Further, the application of the endoscope is not limited to observation and diagnosis. For example, gas may be removed from an intestine by using an endoscope without a cover. That is, the inserting portion of an endoscope without a cover used for testing a colon is covered with a tube such as a sliding tube and the gas in the intestine is removed through a cavity formed by the difference of the inside diameters between the inserting portion and the tube.
In this case, however, since the tube must be previously mounted prior to a test, a job for mounting it is time-consuming and further a drawback arises in that since the insertion of the endoscope without a cover into the intestine is prevented by the tube.
By the way, since the inserting portion of the covering type endoscope has a slender shape, a job for mounting an endoscope cover is relatively difficult. To cope with this problem, there is employed a method of inserting the cover type endoscope into the endoscope cover while the portion of the endoscope cover with which the inserting portion is covered (hereinafter, referred to as an inserting portion cover) is expanded by being fed with air. More specifically, an expansion pump is used to feed air to the inserting portion cover through a tube. On the other hand, air is also fed to the observation window deposed at the extreme end of the endoscope cover type endoscope.
As described above, two kinds of pumps are used in a conventional endoscope cover type endoscope and thus a drawback also arises in that the size and cost of the endoscope apparatus are increased.
Incidentally, the operating unit of the covering type endoscope is connected to a light source through a universal cord and connector. Then, an illuminating light is supplied from the light source to the covering type endoscope through a light guide fiber inserted into the universal cord.
Incidentally, although the universal cord is covered with the universal cord cover of the endoscope cover, the connector portion is sometimes not covered. As a result, a drawback arises in that when the universal cord is mounted to and dismounted from the light source, the connector is contaminated. Further, even if the connector portion is covered, a job for mounting it is relatively difficult because the connector is connected to the universal cord.
Further, the conventional endoscope cover type endoscope also has a drawback in that the inserting portion thereof is insufficiently curved. FIG. 52 is an explanatory diagram showing the state that the inserting portion of an endoscope is mounted to the inserting portion cover of an endoscope cover with a channel, wherein: FIG. 52(a) is a cross sectional view thereof cut in a radius direction; and FIG. 52(b) shows a side cross sectional view thereof cut in a longitudinal direction.
The inserting portion cover 301 of the endoscope cover with a channel includes an air feed tube 302, water feed tube 303 and a suction tube 304 on the upper surface side thereof. Hereinafter, these units contained in the upper surface side of the inserting portion cover 301 are also referred to as a contained unit 310. Further, the inserting portion cover 301 includes an endoscope inserting channel 305 for inserting the inserting portion of the covering type endoscope on the lower surface side thereof. As described above, since these tubes 302, 303, 304 are disposed, the inserting portion 306 of the covering type endoscope is not disposed at the center of the inserting portion cover 301 but disposed eccentrically on the lower surface side of thereof, as shown in FIG. 52.
Note, the outer circumference of the inserting portion cover 301 is covered with a soft inserting portion cover casing 307. Further, a cover extreme end portion 309 for covering the inserting portion extreme end 308 of the covering type endoscope is formed at the extreme end of the inserting portion cover 301.
Incidentally, the extreme end of the inserting portion 306 of the covering type endoscope can be curved so that an observation and diagnosis can be effected in any arbitrary direction. A curving angle of the extreme end when the inserting portion 306 is covered with the inserting portion cover 301 is smaller than a curving angle when the inserting portion 306 is independently curved due to the resistance against the curving of the inserting portion cover 301.
FIG. 53 is an explanatory diagram explaining a curving angle of the inserting portion 306 to which the inserting portion cover 301 is mounted.
The inserting portion 306 includes a soft portion 311, curving portion 312 capable of being curved and hard extreme end portion 308 from the hand side to the extreme end thereof. It is assumed now that the curving portion 312 has a curving radius R1. In this case, as shown in FIG. 53, the inserting portion 306 is curved about 90.degree.. Further, it is assume that the curving portion 312 has a curving radius R2 smaller than the curving radius R1. In this case, the inserting portion 306 has a curving angle of about 180.degree.. As described above, when a curving length is the same, a curving angle is larger as a curving radius is smaller.
Now, it is assumed that the inserting portion 306 is curved in the direction toward the contained unit 310. In this case, as shown in FIG. 52, when it is assumed that the contained unit 310 has a curving radius b, the inserting portion 306 has a curving radius d larger than b. Further, when the inserting portion 306 is curved to a lower surface side and it is assumed that the contained unit 310 and inserting portion 306 have a curving radius a, c, respectively, a&gt;c is established.
The curving radius b of the contained unit 310 in an upper surface direction must be smaller than the curving radius a thereof in a lower surface direction in order that the curving radius c of the inserting portion 306 in the lower surface direction coincides with the curving radius d thereof in the upper surface direction. When this is achieved, however, a curving resistance caused by the contained unit 310 is increased. Therefore, a large force is required to achieve a sufficient curving. On the other hand, when the inserting portion 306 is curved to the lower surface side, the inserting portion cover casing 307 must has a curving radius smaller than that of the inserting portion 306, and it is sufficient that the contained unit 310 having the relatively large curving resistance is curved by a curving radius large than that of the inserting portion 306, and even if the inserting portion 306 is covered with the inserting portion cover 301, the effect thereof to a curving operation is relatively small. After all, a problem arises in that the inserting portion 306 is difficult to be curved to the upper surface side, in particular, in the direction toward the contained unit 310 and thus a small curving radius cannot be obtained.
For example, a curving angle of the inserting portion 306 as a single body is set to 10.degree. in each direction and the inserting portion 306 is covered with the inserting portion cover 301, a curving angle of 170.degree. can be obtained in all directions except the direction toward the contained unit 310 but only a curving angle of 160.degree. is contained in the direction toward the contained unit 310.
Incidentally, the inserting portion cover includes a forceps port communicating with a treatment tool channel. The forceps port is used together with accessories such as a T-shaped tube, thruster, forceps stopper, or the like, or a mouth piece attached thereto, when necessary.
However, the inserting portion cover is sterilized and then disposed of, whereas the accessories attached to the forceps port are repeatedly used. Therefore, a drawback arises in that each time the conventional endoscope covering type endoscope is used, these accessories must be sterilized.
The inserting portion cover of the endoscope cover is formed to have a slender shape and is composed of a cover extreme end portion, flexible cover portion, and endoscope operating unit fixing mouth member disposed from the extreme end thereof. The inserting portion of the covering type endoscope is inserted through the opening of an endoscope inserting channel provided with the endoscope operating unit fixing mouth member and the hand side of the endoscope operating unit fixing mouth member is connected to the extreme end of the operating unit of the covering type endoscope.
The operating unit includes a mounting unit for mounting the universal cord through which the light guide fiber for transmitting an illuminating light, and the like are inserted. The universal cord is inserted from the light source to the operating unit and inserting portion to transmit the illuminating light to the extreme end of the inserting portion. On the other hand, the air feed tube, water feed tube, suction tube and the like are inserted into the interior of the inserting portion cover from a fluid control unit through the opening on the hand side of the endoscope operating unit fixing mouth member of the inserting portion cover.
These tubes are exposed between the inserting portion cover and the fluid control unit and the setting of these tubes are time-consuming. Further, although it is contemplated that these tubes are used in a state in which they are disposed along the universal cord, since the mounting portion of the universal cord is spaced apart from the opening on the hand side of the endoscope operating unit fixing mouth member, the tubes cannot be easily set. Therefore, a drawback arises in that an operation effected on the operating unit is prevented thereby.
Incidentally, a plurality of types of the covering type endoscopes are available in accordance with the purposes to which they are applied. For example, these endoscopes have an inserting portion with a different diameter and length. On the other hand, a plurality of types of the inserting portion covers are available in correspondence with the diameters and lengths of the inserting portions.
Further, a plurality of types of inserting portion covers are applicable to a kind of the covering type endoscope. For example, a forceps channel shared with a suction tube has a different diameter. Further, many covering type endoscopes applicable to a kind of the inserting portion cover are available. For example, a covering type endoscope employing an electrically curving system, angle knob system is available. In addition, there are a plurality of kinds of the number of pixels used in a photographing device provided in the observing optical system of the covering type endoscope.
An operator selects a desired endoscope cover in correspondence with a selected covering type endoscope and mounts the same. However, there are a great many possible combinations of the covering type endoscopes and endoscope covers and thus there is a great possibility that undesired endoscope cover is mounted by mistake.